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1.
Geology of Ore Deposits - For the first time, based on a study of the typomorphic features of placer gold and its distribution patterns, the predicted gold potential of the east of the Siberian... 相似文献
2.
B. E. Peskov A. A. Alekseeva A. E. Nikiforova 《Russian Meteorology and Hydrology》2008,33(10):644-650
The physical-synoptic principles of the automated method of summer precipitation forecasting introduced into operational prognostic practice in 2006 by the decree of the Central Methodical Commission of the Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet) are presented. Beside that, improved modifications of this method, which are automatically updated, are shown. Validation of those updates based on observational data collected in 2004 has shown improvement of all major criteria of forecasts efficiency. The performed improvement is based on the more detailed quantitative realization of mechanism of various showers formation (including heavy rainfalls). 相似文献
3.
D.?Yu.?TsvetkovEmail author S.?Yu.?Shugarov I.?M.?Volkov N.?N.?Pavlyuk O.?V.?Vozyakova N.?I.?Shatsky A.?A.?Nikiforova I.?S.?Troitsky Yu.?V.?Troitskaya P.?V.?Baklanov 《Astronomy Letters》2018,44(5):315-323
We present the results of our UBVRI photometry for the type II-P supernova SN 2017eaw in NGC6946 obtained fromMay 14 to December 7, 2017, at several telescopes, including the 2.5-m telescope at the CaucasusHigh-Altitude Observatory of the SAIMSU. The dates andmagnitudes atmaximumlight and the light-curve parameters have been determined. The color evolution, extinction, and peak luminosity of SN 2017eaw are discussed. The results of our preliminary radiation–gasdynamic simulations of its light curves with the STELLA code describe satisfactorily the UBVRI observational data. 相似文献
4.
F. G. Ajupov R. I. Gumerov V. B. Kapkov B. K. Bagildinsky V. N. Ershov K. N. Naumov O. Yu. Nikiforova T. R. Kirijan Yu. G. Ostrensky Yu. S. Streletsky B. N. Smirnov A. A. Pozhalov V. D. Shkutov G. I. Pinigin A. V. Sergeev O. E. Shornikov 《Astrophysics and Space Science》1991,177(1-2):219-223
The results of investigations and observations with classical meridian circle MK-200 and photographic vertical circle (PVC) after its modernization and automation are discussed. The data concerning the stability of the instrumental system and the flexure of the Pulkovo Horizontal meridian circle (HMC) are given. New work on the establishment of in axial meridian circle in Nikolaev, Ecker meridian circle and reflecting one in Pulkovo is mentioned. 相似文献
5.
The internal structure of placer gold depends on its residence time under exogenetic conditions. Two types of placer gold
are distinguished in the middle Lena River basin by typomorphic features. Gold of distal transfer (type I) is characterized
by recrystallized structure, deformation lines, and thick high-fineness rims indicating long-term residence under exogenetic
conditions; and multifold redeposition in transitional reservoir rocks. Gold of proximal transfer (type II) is characterized
by a vague zonal structure, thin or discontinuous high-fineness rims, granulation, and disintegration structures indicating
short-term residence time under the exogenetic conditions. Gold of proximal transfer is spatially confined to the zones of
ancient long-living faults. Thus, it is possible to suggest that this type of gold might have derived from local Middle Paleozoic
or Mesozoic gold sources. 相似文献
6.
Doklady Earth Sciences - For the first time, the concentrations of 11 polycyclic aromatic hydrocarbons (PAHs) in urban sealed soils (ekranozems) and asphalt concrete pavement in eastern Moscow have... 相似文献
7.
The variability of parameters of the Antarctic ozone anomaly is studied using data of the TOMS/OMI satellite monitoring of the ozone layer, MERRA-2 reanalysis, and balloon sounding of the vertical distribution of ozone and temperature at the South Pole. The dynamic processes in the Antarctic stratosphere which define conditions for the significant ozone layer destruction are analyzed. Despite the decrease in the concentration of ozone-depleting substances, the significant ozone loss in the recent 8 years was observed in the Antarctic in 2011 and 2015. 相似文献
8.
Typomorphic features of placer gold in the eastern Siberian Platform were studied to determine its genesis. It was established
that this region contains abundant alluvial bar placers, which were formed mainly by the erosion of gold reservoirs of different
ages. Discovery of gold with the points of eolian reworking in the Quaternary sediments allows us to predict the eolian gold
placers in individual areas of the northeastern and central parts of the eastern Siberian Platform. Identification of two
types of gold on the basis of typomorphic features in the Cenozoic deposits indicates that placer gold was mainly derived
from the Precambrian sources spatially confined to the exposure of ancient basement, as well as from local ore occurrences
related to the Mesozoic tectonomagmatic activation. Thus, two main stages of ore formation (Precambrian and Mesozoic), were
substantiated for the first time in the eastern Siberian Platform. 相似文献
9.
Z. S. Nikiforova B. B. Gerasimov E. G. Glushkova A. G. Kazhenkina 《Geology of Ore Deposits》2013,55(4):265-277
The data on typomorphism of placer gold and its localization in the eastern Siberian Platform have been integrated for the first time. The alluvial, pseudolode, and eolian morphology of gold determines the origin of placers, which is explained not only by hydrodynamic but also by eolian processes. The recent and older alluvial (Au-bearing reservoir rocks in the second case), as well as eolian (unconventional type), genetic types of placers are recognized in the given territory. Precambrian and Mesozoic stages of ore formation are distinguished by the set of typomorphic attributes of placer gold (chemical composition, microinclusions, internal structure, etc.). On the basis of distinguishing features of placer gold, Precambrian lode deposits of great depth spatially related to outcrops of the basement have been forecasted for the first time and classified into low-sulfide gold-quartz, Au-bearing banded iron formation, Au-Cu porphyry, and Au-PGE types. The inferred shallow-seated gold-silver and gold-sulfide-quartz disseminated deposits occur locally and are related to the Mesozoic tectonomagmatic reactivation. The elaborated methods and approaches to the study of placer gold typomorphism in the eastern Siberian Platform also could be helpful in providing insights into placer origin, and forecasting and prospecting gold deposits on the East European Platform, which is close to the Siberian Platform in geological evolution. 相似文献
10.
Z. S. Nikiforova 《Lithology and Mineral Resources》2003,38(6):547-551
The distribution of eolian gold in various Proterozoic–Cenozoic sediments on the East European Platform is considered. Eolian placers of the Timan Ridge are characterized by specific features: significant areal distribution and consistent strike of the thin (0–30 cm) productive bed. Prospecting criteria of eolian gold placer in the study territory can be the presence of gold flakes and other minerals with signs of eolian reworking, specific structure of productive bed, deflation structure of relief, and characteristic lithological composition of sediments. It is concluded that since gold flakes with eolian reworking make up high metal concentrations, such as placer deposits in the Timan Ridge, eolian placers of different age may be found on the East European Platform. 相似文献